Update draft-js to 0.11.0 or newer

[lukaszstalmasinski]

Do you have plan to update draft-js library?
It is important to me because of draft-js licence has been changed.

[testn]

It should also be updated because draft-js relies on older version of fbjs which pulls in the old core-js which is already obsoleted

| `-- rc-editor-mention@1.1.13
|   `-- draft-js@0.10.5
|     `-- fbjs@0.8.17
|       `-- core-js@1.2.7